The present invention relates to a device for discharging the contents of various collapsible packages such as the tubes in which toothpaste, adhesive pastes, grease paints, and the like are commonly sold. More particularly, this invention relates to an improvement in the type of dispensing apparatus for dispensing the contents of collapsible packages which utilize a pressure plate for compressing the collapsible package to dispense the contents thereof.
Many types of dispensing apparatus are known in the prior art for dispensing the contents of collapsible packages, but the type in which a pressure plate is utilized to compress the package is believed to be most preferable since it lends itself to a simpler construction having fewer parts than other package discharging arrangements, such as apparatus using a travelling pair of nip rollers between which the package is compressed.
Representative of the prior art dispensing apparatus which utilize pressure plates are U.S. Pat. Nos. 1,320,275; 1,558,195; and 2,850,212. In the U.S. Pat. No. 1,320,275 a device for extruding paste from tubes is disclosed wherein a pressure plate is hinged to a frame so as to form a pair of jaws with a base plate between which the collapsible tube can be compressed. While this patent does disclose a simple device for dispensing the contents of a collapsible tube, it has several deficiencies inherent in its manner of construction. Firstly, since the pressure plate is hinged to form a pair of jaws, the device can only be utilized with the type of tapered tube conventionally used with toothpaste and is not suitable for use with blunt ended packages. Furthermore, the arrangement of U.S. Pat. No. 1,320,275 merely utilizes a single pressure applying member for causing displacement of the pressure plate such that uniform pressure cannot be applied and difficulties in discharging the total contents of the package result due to deflections of the hinged pressure plate that can occur in areas at which no actuating pressure is applied.
In U.S. Pat. No. 1,558,195, the above-noted disadvantage which results from the pivotal mounting of a pressure plate is avoided, but since the pressure plate disclosed therein is arcuate in shape and since pressure is applied for compressing the package only at a single central point, all of the contents of the tube cannot be discharged since the arcuate contour of the pressure plate prevents totaly compression of the package against an oppositely facing wall of the housing, while the single mounting point prevents uniform pressure application and enables a swinging of the pressure plate with the resultant effect that a portion of the contents of the package can become trapped in the bottom half thereof.
In U.S. Pat. No. 2,850,212 a fluid dispensing apparatus is shown having a jaw arrangement similar to that of U.S. Pat. No. 1,558,195 wherein the pressure applying arm is provided with a roller for engaging the rear of the pressure plate and the pressure arm is angled rearwardly so that pressure is applied to the bottom half of the package, thereby avoiding the previously noted problem with respect to part of the contents becoming trapped in the bottom of the bag. However, disadvantages still persist in the arrangement disclosed in U.S. Pat. No. 2,850,212 since but a single pressure applying arm is utilized to compress the package against the wall of the housing, such that uniform pressure cannot be applied to the package and the forward end of the pressure plate is free to swing upwardly preventing the entire contents to be forced from the package, no force being directly appliable to the part of the pressure plate contacting the forward discharge end of the package.
In addition to the above-noted disadvantages, the prior art dispensing arrangements had limited flexibility with regard to the number of sizes of packages that could be used in a particular device due to the fact that but a single pressure arm was provided.
Accordingly, it is an object of the present invention to provide a dispensing apparatus for discharging the contents of collapsible packages which is of a simple construction having a minimum of working parts.
It is a further object of the working invention to provide an improvement is dispensers for collapsible packages of the type utilizing a pressure plate for compressing the package against a wall member having the capability of accepting packages of varying sizes and shapes.
It is still another object of the present invention to provide a dispensing apparatus that dispenses the contents of collapsible packages through the use of a pressure plate which compresses the package against a wall member which will ensure that complete discharge of the contents of the package will be obtained.
These and other objects of the present invention are obtained in a preferred embodiment of the present invention through the provision of a housing which is mountable to a supporting surface within which the collapsible package can be held with its discharge outlet extending therefrom. Additionally, a pressure plate is positioned within the housing extending longitudinally therein so that it can be urged towards a wall of the housing to collapse the package between the pressure plate and the wall under action of an actuating means. This actuating means includes a pair of pressure arms which are pivotally connected at a first end to a wall of the housing and are engageable at their opposite end to spaced portions of the pressure plate so that displacement of an operating means will pivotally swing the pressure arms along the pressure plate, causing displacement of the pressure plate towards the wall of the housing with a resultant collapsing of the package and a dispensing of its contents.
Other features of the preferred arrangement advantageously provide rollers on the pressure plate contacting ends of the pressure arms so as to reduce friction between the pressure arms and the pressure plate, and a cap of flexible material having a dispensing slit at one end is provided for mounting upon the discharge outlet of the collapsible package for preventing leakage and enabling a desired uniform distribution of the dispensed material.
These and further objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a single embodiment in accordance with the present invention.